Ana Lucia Campana Perilla

• Campaña Perilla, Ana Lucia; Joudeh, Nadeem; Høyer, Henrik; Røyne, Anja; Linke, Dirk & Mikheenko, Pavlo (2020). Probing van der Waals and magnetic forces in bacteria with magnetic nanoparticles, In  2020 IEEE 10th International Conference on “Nanomaterials: Applications & Properties” (NAP – 2020).  IEEE.  ISBN 978-1-7281-8506-4.  Article.  s 01NSSA03-1 - 01NSSA03-5 Fulltekst i vitenarkiv. Vis sammendrag

  Bioinspired metal-based nanoparticles have potential uses in many applications, but before a possible commercial exploitation, it is important to clarify the pathways of their production and deposition inside the organisms, for example in bacteria. The technique of magnetic force microscopy (MFM) could be used to evaluate the nanoparticles magnetic properties, in addition to allowing tracing their location inside or outside of bacteria, which could help to understand pathways of their biosynthesis. In this work, using MFM and analyzing the interaction of magnetic tip with nanoparticles and bacteria imbedded in resin at different heights above the surface, and comparing gradients of forces recorded by magnetic and non-magnetic tips, a condition was found, which allows to measure pure magnetic response of Pd-Fe nanoparticles. For these nanoparticles, the interplay between magnetic and van der Waals forces is described at small distances to the surface. Experimental data are compared with simulations, based on the calculation of the distribution of magnetic field around a nanoparticle, which defines magnetic force acting on the MFM tip.

• Campaña Perilla, Ana Lucia; Sotelo, Diana Camila; Oliva, Hector Alfonso; Aranguren, Andres; Ornelas-Soto, Nancy; Cruz, Juan Carlos & Osma, Johann (2020). Fabrication and Characterization of a Low-Cost Microfluidic System for the Manufacture of Alginate–Lacasse Microcapsules. Polymers.  ISSN 2073-4360.  12(5) . doi: 10.3390/polym12051158 Vis sammendrag

  The development of microfluidics-based systems in the recent years has provided a rapid and controlled method for the generation of monodisperse microencapsulates for multiple applications. Here, we explore the design, manufacture, and characterization of a low-cost microsystem for the encapsulation of the fungal laccase from Pycnoporus sanguineus CS43 in alginate microcapsules. Multiphysics simulations were used to overview the fluid behavior within the device and estimate the resulting capsule size. Polymethylmethacrylate (PMMA) sheets were used for final microsystem manufacture. Different flow rates of the continuous (Qc) and discrete (Qd) phases in the ranges of 83–293 mL/h and 1–5 mL/h, respectively, were evaluated for microcapsule fabrication. Universal Serial Bus (USB) microscope and image analysis was used to measure the final particle size. Laccase encapsulation was evaluated using spectrophotometry and with the aid of fluorescent dyes and confocal microscopy. Results showed microcapsule size was in the range of 203.13–716.00 μm and Qc was found as the dominant parameter to control capsule size. There was an effective enzyme encapsulation of 65.94% with respect to the initial laccase solution.

• Lopez-Barbosa, Natalia; Campaña Perilla, Ana Lucia; Cruz, Juan Carlos; Ornelas-Soto, Nancy & Osma, Johann (2020). Enhanced Catalytic Dye Decolorization by Microencapsulation of Laccase from P. Sanguineus CS43 in Natural and Synthetic Polymers. Polymers.  ISSN 2073-4360.  12(6) . doi: 10.3390/polym12061353 Vis sammendrag

  Polymeric microcapsules with the fungal laccase from Pycnoporus sanguineus CS43 may represent an attractive avenue for the removal or degradation of dyes from wastewaters. Microcapsules of alginate/chitosan (9.23 ± 0.12 µm) and poly(styrenesulfonate) (PSS) (9.25 ± 0.35 µm) were synthesized and subsequently tested for catalytic activity in the decolorization of the diazo dye Congo Red. Successful encapsulation into the materials was verified via confocal microscopy of labeled enzyme molecules. Laccase activity was measured as a function of time and the initial reaction rates were recovered for each preparation, showing up to sevenfold increase with respect to free laccase. The ability of substrates to diffuse through the pores of the microcapsules was evaluated with the aid of fluorescent dyes and confocal microscopy. pH and thermal stability were also measured for encapsulates, showing catalytic activity for pH values as low as 4 and temperatures of about 80 °C. Scanning electron microscope (SEM) analyses demonstrated the ability of PSS capsules to avoid accumulation of byproducts and, therefore, superior catalytic performance. This was corroborated by the direct observation of substrates diffusing in and out of the materials. Compared with our PSS preparation, alginate/chitosan microcapsules studied by others degrade 2.6 times more dye, albeit with a 135-fold increase in units of enzyme per mg of dye. Similarly, poly(vinyl) alcohol microcapsules from degrade 1.7 times more dye, despite an eightfold increase in units of enzyme per mg of dye. This could be potentially beneficial from the economic viewpoint as a significantly lower amount of enzyme might be needed for the same decolorization level achieved with similar encapsulated systems.

• Campaña Perilla, Ana Lucia; Florez, Sergio Leonardo; Noguera, Mabel Juliana; Fuentes, Olga; Ruiz, Paola; Cruz, Juan Carlos & Osma, Johann (2019). Enzyme-based electrochemical biosensors for microfluidic platforms to detect pharmaceutical residues in wastewater. Biosensors.  ISSN 2079-6374.  9(1) . doi: 10.3390/bios9010041 Vis sammendrag

  Emerging water pollutants such as pharmaceutical contaminants are suspected to induce adverse effects to human health. These molecules became worrisome due to their increasingly high concentrations in surface waters. Despite this alarming situation, available data about actual concentrations in the environment is rather scarce, as it is not commonly monitored or regulated. This is aggravated even further by the absence of portable and reliable methods for their determination in the field. A promising way to tackle these issues is the use of enzyme-based and miniaturized biosensors for their electrochemical detection. Here, we present an overview of the latest developments in amperometric microfluidic biosensors that include, modeling and multiphysics simulation, design, manufacture, testing, and operation methods. Different types of biosensors are described, highlighting those based on oxidases/peroxidases and the integration with microfluidic platforms. Finally, issues regarding the stability of the biosensors and the enzyme molecules are discussed, as well as the most relevant approaches to address these obstacles.

• Kaur, Amandeep; Funderburk, Karen; Campaña Perilla, Ana Lucia; Puente, Patricia & Ríos-Soto, Karen R. (2019). A household model of German cockroach infestations and their effects on symptoms of atopic asthma. Letters in Biomathematics.  ISSN 2373-7867.  6(2), s 1- 26 . doi: 10.1080/23737867.2019.1685920 Vis sammendrag

  Asthma is a chronic respiratory condition which affects 25 million people in the United States. Improper extermination of cockroaches and their associated allergens significantly increases the occurrence of atopic asthma, a type of asthma stemming from exposure to allergens. To date, dynamical studies of cockroach infestations and their effects on atopic asthma have not been examined. Here we develop a novel mathematical model, with households as the model unit, to study the dynamics of cockroach infestations within a neighbourhood and how they impact the prevalence of asthma. The focus of this study is to evaluate the impact of extermination and removal of allergens in a household containing an individual with recurrent atopic asthma. Through analysing our model, the basic reproduction number for cockroach infestations was calculated and we were able to determine conditions under which cockroaches and asthma can be eliminated from a community containing infested houses. From the presence of a backward bifurcation, we are able to show that it is more effective to prevent infestation of cockroaches than attempting to remove them post-infestation. These conclusions could potentially assist in educating the general public about the importance of pest control and its relationship with asthma.

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• Campaña Perilla, Ana Lucia; Joudeh, Nadeem; Høyer, Henrik; Røyne, Anja; Linke, Dirk & Mikheenko, Pavlo (2020). Probing van der Waals and magnetic forces in bacteria with magnetic nanoparticles. Vis sammendrag

  Bioinspired metal-based nanoparticles have potential uses in many applications, but before a possible commercial exploitation, it is important to clarify the pathways of their production and deposition inside the organisms, for example in bacteria. The technique of magnetic force microscopy (MFM) could be used to evaluate the nanoparticles magnetic properties, in addition to allowing tracing their location inside or outside of bacteria, which could help to understand pathways of their biosynthesis. In this work, using MFM and analyzing the interaction of magnetic tip with nanoparticles and bacteria imbedded in resin at different heights above the surface, and comparing gradients of forces recorded by magnetic and non-magnetic tips, a condition was found, which allows to measure pure magnetic response of Pd-Fe nanoparticles. For these nanoparticles, the interplay between magnetic and van der Waals forces is described at small distances to the surface. Experimental data are compared with simulations, based on the calculation of the distribution of magnetic field around a nanoparticle, which defines magnetic force acting on the MFM tip.

Se alle arbeider i Cristin